I know nothing - HELP!

Seriously, I'm brand new to this stuff and have never taken a class or anything. In fact, I just found out what a breadboard/protoboard was the other day and ordered one on ebay. So again, I know nothing about this stuff but I'm anxious to learn.

I want to make a circuit that can be set to light an LED and set off a buzzer at repeated intervals every 12 hours. I would also like to have the LED and buzzer turned off with the push of a button but to have it go off again 12 hours later. I want all of this to be on a very small scale (about the size of a quarter).

As mentioned, I bought a breadboard and have also purchased some 555 timers, 4020 ripple-carry binary counters, a 6 mm mini push button on/off, a 30 mm x 15 mm 8-ohm speaker, jumper wires, and a pack of small 1 volt watch batteries. I bought this stuff just by using logical reasoning in thinking about the circuit but again, I have no idea if this is at all what I need as I've never done anything like this at all.

So the question: What else will I need? How do I build this? If I'm in over my head (and I feel like I am), where can I go to get someone to build this for me for a small fee? How much would it cost to have someone more experienced do something like this?

An MCU is a microcontroller unit, i.e., a computer on a chip. They are available in several flavors, e.g., PIC, PICAXE, Arduino, Basic Stamp, etc. They can be programmed to do quite a lot of different things like timers, LED flashers, sound makers, as well as read a variety of sensors and clocks.

That is not to say that what you want cannot be done with separate components, maybe even with some of the ones you have. However, without using SMD (surface mount devices), the assembly will be bigger than a quarter.

Great, thanks! I'll keep this thread here and bump it from time to time until someone offers to help me out (i.e. do it for me because I have not a clue). I'll post a similar thread in some of the other categories.

Thanks again guys! And if you're interested in helping in exchange for some components/payment, let me know.

Great, thanks! I'll keep this thread here and bump it from time to time until someone offers to help me out (i.e. do it for me because I have not a clue). I'll post a similar thread in some of the other categories.

Thanks again guys! And if you're interested in helping in exchange for some components/payment, let me know.

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If you want to get into electronics, I would suggest you give it a go for yourself...if you look up "pickit2", you will see an affordable kit that has both the programmer, software, and prototyping board.

Everyone fluent in PIC C/assembly will be more than happy to help you get this done. It's not too complicated, but there are a few subtle things that'll need to be worked through.

If I had to write the pseudocode (topological outline of what the code does as opposed to what it is):

... I want all of this to be on a very small scale (about the size of a quarter).
... where can I go to get someone to build this for me for a small fee?

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Not sure what you mean by "small" fee, but I doubt you'll find anyone to do this for a fee you'll be happy with. Someone may take it as a charitable project, pro bono, but good luck with that.

I don't know how you could keep it that small, but you might consider a hack solution. By that I mean finding a commercial timer you like and hacking in a light, alarm and switch that meet your specific needs.

How long is the LED suposed to stay on every 12 hrs.? How much of the ckt goes into the quarter, speaker, batteries, & timer? How thick is the stack of quarters? Use one 555 as clock for 4020 counting to 12 hours, trip another 555 for alarm duration, 3rd 555 as oscillator to drive speaker. switch to reset everything. What part of the world are you in- just in case of shipping?